After years of putting up with crappy “boom boxes” in my shop, I finally sprang for a used Harmon Kardon receiver that I found on craisgslist. I have to say, it’s great to have nice music out there. I use it to drive some KLH speakers, and I keep the receiver in a cabinet to keep most of the dust away from it. For the geeks of the crowd, I’m running iTunes 7.x across a WiFi network and everything is great.
The only disappointment is FM reception. I live in the SF Bay area, so reception should be fine. In reality, though, every station seems to have static. Even the large stations are un-listenable (hey, like that word I just invented?)
Does anyone have a favorite FM Antenna they would recommend? I have problems whether I’m running power tools or not. My peltor headset seems fine, but I don’t want to wear that when I’m doing hand work.
Thanks
DJS
“Honey, will you please make some sawdust and track it across the carpet?”
“Yes, dear…”
Replies
You could try grounding your unit, and I found antenna orientation to sometimes be inportant.
Pedro
There is a table radio called Tivoli One that is sold at Target and was designed by the guy who founded KLH.
It solved all my FM reception problems and the design should be in the Museum of Modern Art.
Only problem it costs $120.00 but it has the best sound you will ever hear from a table radio.
"There is a table radio called Tivoli One that is sold at Target and was designed by the guy who founded KLH. It solved all my FM reception problems and the design should be in the Museum of Modern Art."
Henry Kloss started a bunch of companies - Acoustic Research (AR), KLH and Advent among others. When he was at Advent in the 1970s, he designed the Model 400 FM radio. After looking at the Tivoli, I suspect they share some DNA. I have an Advent that I listen to every morning, and it's probably one of the best FM radios ever built. That's all it does, though - just FM, no stereo, no AM, no nothing.
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Do you have any antenna on the reciever now at all, or are you just using that little dinky cylinder thing that Harmon Kardon hung on the back side? My experience is that little cylinder doesn't do much good. The cheapest upgrade is a simple dipole antenna like what you can buy at Radio Shack for a couple bucks. They work pretty well unless you're in a fringe area. You can even make your own with scrap wire, here's a page that describes out to do it: http://www.tackyliving.com/article.php?id=61
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The "cylinder thing" on the back is the AM antenna.
"I cut this piece four times and it's still too short."
DJS, In the Bay area, a single 3' wire attached to either of the FM antenna terminals should get 95% of the stations between San Jose and Sonoma. Radio Shack has a standard dipole antenna for $4.95 that should do everything you need. Rich
I currently have a Terk antenna attached to teh 75ohm connection on the back. Doesn't seem to do any good.
http://www.amazon.com/FM-Edge-Dual-Drive-Amplified-Antenna/dp/B000EA1IAM/sr=8-37/qid=1171921871/ref=sr_1_37/002-6777672-5867264?ie=UTF8&s=hi
no dice..."Honey, will you please make some sawdust and track it across the carpet?"
"Yes, dear..."
Fluorescent lights? In a basement shop? You may need to remote the antenna out of the shop away from the fluorescent lights. If you're gettng the static on all stations, then there is most likely some environmental obstical in the way.
If it's a grounding problem, then there is something more serious going on, I think.
RegardsBob @ Kidderville Acres
A Woodworkers mind should be the sharpest tool in the shop!
I live on the peninsula between SF and San Jose, so it's all pretty darn flat. Shop is stick frame construction, (2-car garage) composite shingle roof. with 4 flourescent fixtures. With the lights out...no real difference in reception.
For those that live in the area, I get the most problem with KKSF. KFOX is sproadic- some days it's good, some days it isn't.
Will try the extended cable trick next."Honey, will you please make some sawdust and track it across the carpet?"
"Yes, dear..."
I don't know how your shop is set up but FM is line of sight- if you can see the tower, you should be able to get good reception unless the building is metal or there's a big building between your receiver and the tower. Winegard makes all kinds of antennas and one of their cheapest FM antennas works pretty well if you're not in a dead spot. Try connecting the Terk to a longer piece of coax and move it around your shop- you may find the sweet spot.
DJS: Static may not be from the reception it could be dirt in the "pots" the volume and bass/treble controls. Try some contact cleaner though the openings while rotating them a bunch of times. I'm over in Bezerkeley and FM comes in easy.
Duke
Support the Troops, Support your Country
Support Western Civilization:
Fight Islamofascism
unfortunately, that's not it. THe CD player and cassette deck are 100% crystal clear, as is the iTunes connection (airport Expresss) Today I can get KFOX fine, but still static on KKSF. BUmmer for me, as I'm a jazz fan."Honey, will you please make some sawdust and track it across the carpet?"
"Yes, dear..."
Sorry to say but KKSF comes in fine here. Have you tried the new HDFM? Great sound in my opinion although I've heard others say nay on the sound quality. KDMSupport the Troops, Support your Country
Support Western Civilization:
Fight Islamofascism
This is a fairly broad subject, but a few bullet points:
1. A crappy receiver with a good antenna will ALWAYS sound better than a good receiver with a crappy antenna.
2. None (repeat none) of the inside antennas (Terk, rabbit ears, etc) are worth a damn.
3. In urban areas it is not sensitivity, but selectivity that is important.
4. Physics dictates that to receive a broadcast FM signal, the antenna should resonate at 1/2 the wavelength of the carrier wave (~100 MHz). The average FM carrier wave is about 3 meters, so the antenna elements will be about 1.5 meters (5 feet) in size. Hence #2, above.
5. Simple dipoles (Y or T shaped wires) are generally not very directional (selective). Thus in urban areas they are not very good. The usual problem in urban areas is interference- an overpowered FM music station bleeds its harmonics into the station you are interested in. Another problem is multipath reflection, when a radio signal is reflected off a building or tower and part of the signal arrives late and a bit out of phase with the main wave. This causes ghosting on over the air TV, and static interference with FM audio. Strongly directional antennas will reject these interfering waves resulting in much cleaner reception.
6. A log linear or Yagi design works best. These are the "old fashioned" type of chevron shaped antennas that used to sprout from every suburban roof in the days before cable. You can buy a Radio Shack or Winegard for ~$70 for FM broadcasts; mounting will run another $20.
7. The easiest way I have found to mount these antennas is on a cast iron vent pipe where it exits through the roof. Make sure to ground it via a metal grounding stake at least 24 in deep with 10 g conductor. Putting the antenna outside will also minimize any RF interference you are getting from your power tools.
Just my 2p,
Glaucon
If you don't think too good, then don't think too much...
Glaucon:
You touched on a lot of good points and while I'm not a pro at this, I do follow the logic/physics. And there is one point you made about antenna being essentially an integral length of the signal length - and I follow that.
But wasn't that problem solved - particularly for emergency services FM band radios by putting what is called a "loaded" antenna on the radio. Also known as "rubber ducky" antennas, they dramatically reduced the physical length of the antenna. I understand it is essentially a coil that has been "tuned." And don't some of these "wizard" signal boosters use that technology? - and don't some also include as you have mentioned signal boosters? So some of these little antenna devices that sell from $25 to close to $100 use that technology to enhance the FM signal and could work in the right circumstances?
Again, I'm at the edge - and maybe beyond my knowledge base, so please enlighten me on this. Thanks!
Ed
Edited 2/20/2007 1:10 pm ET by ETG
Ed,Unfortunately, the points I made in an earlier post are really a consequence of physics... and cannot be repealed. The issue has to do with the ability of an antenna to resonate with a standing wave of the carrier frequency. If you think of a radio wave as a sine wave- starts at zero, reaches full amplitude at 90 degrees, then back to zero at 180 degrees, then negative full amplitude at 270 degrees, then to zero at 360 degrees, it turns out that you can have half of that wavelength resonate along an antenna element from (say zero degrees to 180 degrees).So the question is, how long is half a wavelength? Well the FM broadcasr range runs from 87 MHz to 107 MHz. The formula for wavelength is c=L*N, where c is the speed of light, L is the wavelength and N is the frequency. If c=300,000,000 meters/sec and N=100,000,000 Hz, then L is 3 meters, and half of L would be 1.5 meters, or about 5 feet. This would apply to a high gain, directional log-periodic or Yagi antenna. The rubber ducky types are typically 1/4 of the carrier wavelength (~2.5 feet would be optimal), but they do not actually resonate at the tuned frequency, but rather detect the electric fields associated with the carrier wave. This is a substantial trade off in both gain and directionality, although they are portable and convenient.As for emergency services, it depends on what bandwidth they transmit upon. If it is the 900 Mhz band, then L would be 0.33 meters and the antenna should be 0.17 meters, or about 7 inches. The length of the antenna is dictated (not guided but dictated) by the properties of the carrier wave. There is no way to get round this. If there was, cell phone companies and TV/radio transmitters would not be the huge, expensive toweres that they are, and the DoD would not spend billions to construct huge antennas to communicate with submarines using ultra low frequencies. It is also why ham radio oerators build towers in their backyards to transmit.The mini antennas (Terks, etc.) are more a triumph of marketing than of technology. It is possible to do some tricks to improve ergonomics, but you cannot alter the tyranny of the physics. For example (as was asked in an earlier post), you can receive a broadcast FM signal with a roof top antenna. You can then convert that content into a 2.4 Ghz (cordless phone BW) signal to rebroadcast to receivers or head sets inside a home or business. Since the frequency is much higher (and has a shorter range), the antenna is much smaller. If the signal is rebroadcast as a digital, rather than an analog transmission, interference will be minimized.In the end, my original advice stands. If you have invested in an HK receiver and speakers, your best result for FM reception will be with a roof mounted antenna. For less than $100 and an afternoon's work, you will get an optimal result.Glaucon
If you don't think too good, then don't think too much...
What I'm talking about is down at the 33, 39 and 46 mh range - and the antenna, particularly for the 33 range were close to 3 ft! Apparently the rubber ducky - which replaced all that length by wrapping that 3 ft. into a tiny coil results in a 6 inch antenna. And they work! So the laws of physics are not violated - they just use a different technique. And don't those little "wonder antennas" sold by Radio Shack do the same thing.
I'm sitting here right now with my receiver getting strong signals from many dispatch centers with a rubbber ducky - all down at the 39 and 46 mh range.
I think it depends on what you are receiving- stereo with side bands, terrain and distance. In my experience, and that of many others, receiving high fidelity stereo reception in a crowded urban environment such as the Bay area- with its hills, buildings and towers requires a better antenna than a rubber ducky. What you want is a reasonably high gain, very directional Yagi or log periodic to deal with endemic multipath relection/interference. I really don't think a rubber ducky or a folded dipole will solve the original poster's problem, which is what my answer was directed towards doing.Glaucon
If you don't think too good, then don't think too much...
Try XM. My son, who is a trucker, is crazy about it. Over a hundred stations - each with its own type of programming. Your antennae must be exposed but it will go through glass. It comes via satellite.
Terk's have very poor reputations for performance. In general they seem designed primarily for looks and to score high in "industrial design" (i.e., cosmetics) reviews.
It's not surprising the HK receiver won't work well without a good antenna. Unlike portables, it'll be well-shielded, and if it doesn't get a good signal on the ANT input, you won't hear anything.
You need to get an antenna outside. Any good VHF TV antenna will work, although they be bigger than what you need since they need to work down to TV channel 2, which is much longer in wavelength than the FM band.
From your location, something like an Antennacraft FMSS would probably work great (and is cheap): http://www.antennacraft.net/pdfs/FMSS.pdf
You can pick it up at http://www.solidsignal.com/prod_display.asp?PROD=FMSS
You'll need to get some RG-6 coax cable, an exterior matching transformer (goes between the antenna and the cable), and a grounding block as well.
I've put some very nice stereo equipment in my shop since I spend most days there. Reception is very poor around here so I finally sprung for a roof-mount Yagi wired with RG-6 co-ax and mounted on a rotator. Reception is now great, much better than what the folded dipole someone linked to provided. Got the antenna at Radio Shack on sale for about $60. The rotator is a little pricier and harder to find, but isn't really a neccessity.
It is also possible that your HK has tuner issues.
The static may be coming from some of your equipment. Battery chargers and fluorescent lights are a common source of static.
John White, Shop Manager, Fine Woodworking Magazine
John,This is true as far as it goes, but better quality receivers are usually well shielded. The problem arises when the antenna is in the shop itself- picking up all the interference in the ambient environment and feeding it directly into the RF stage of the receiver. If the antenna is located outside the shop (e.g. on the roof), and if the lead-in is coaxial, this problem is avoided. In a pinch, you can also mount a preamp on the antenna to gain the signal before enterring the shop, but this is generally only necessary in fringe reception areas.Glaucon
If you don't think too good, then don't think too much...
The best way to get good FM reception is to listen to cd's. There doesn't seem to be anything worth listening to on FM here on the southern Oregon coast.
Paul
Since some of you guys seem to know quite a bit about this...... I have a similiar problem in my shop. I like to wear a portable radio on my belt with noise a noise cancelling headset. I do this when listening to talk programs on public radio. With my very poor hearing, this is the only way I can understand what is being said. The headset doesn't protect my ears when using machinery but is fine for bench work. The problem for me is static and fade as I move around in the shop. My building has steel siding so I suspect that could be a contributing factor. My boom-box fm radio works fine as long as it's near the window but without the headset, I can't understand speaking. Is there some sort of fm booster that I can get that will work within my building? I've asked at places like Best Buy and get blank stares. The little devices used in car systems that broadcast one's ipod into the car radio have about a 10 foot range. My shop is much bigger than that. Any ideas? Thanks.
check with the X10 folks (http://www.x10.com) to see if they've got anything that will work for you. I know they've got a transmitter to send audio to remote speakers, but don't know if they've got anything that will help you with a battery-operated portable radio. For those who get poor reception in a basement shop but good reception upstairs, one of these transmitters for wireless connection to speakers might do the trick. The upstairs audio system can be controlled from the shop with the included remote (according to the website, although I've had no personal experience with this device).
Sirius satallite radio solved all my listening problems, 24 hour jazz where ever I go.
Pedro
Cordless headphones might solve your problem. I used to use a 900mHz set when out doing lying under a tree in the orchard and could get good reception up to 150 feet from base inside the house.Set up your radio in a spot with good reception and plug the base unit into the headphone jack. Tune the headset to the base unit and you're good to go. There was a volume control on the headset.
Thanks, I'll check into that. I didn't know there was such a thing as cordless headphones.
Sapwood,
I would second the previous poster's recommendation about wireless headphones. You could put your radio close to a window or where it gets the best signal, and walk around your shop with the wireless headphones. I think the transmitter that sends the signal to the headphones will attach to an input on your radio. They are designed to work indoors and at great distances from the transmitter. I have seen them at crutchfield (http://www.crutchfield.com) Crutchfield has great customer service, and if the headphones don't work out for you or don't do what you need them to, you can return them for a full refund.
Good luck,
Lee
Edited 2/21/2007 10:01 am by mapleman
Thank you for that link. I'll check it out.
Do you get cable TV?
Years ago I lived in Marin in a location with zero FM reception. The cable TV signal also carried FM. I think this was location specific (i.e. they sent us FM because we could get nothing where we were). It's worth a try, just touch the cable to a metal part of your radio, if it comes in clear, get a splitter and go. Good luck!
I also have a HK reciever. Try pushing the button that says FM Mono and see what happens. For some reason my FM only comes in when this is selected, otherwise every station is static.
We live a little farther south in the Bay Area (Sunnyvale) and our favorite station is KDFC (classical). Their transmitter is actually above Sausalito, so SF and the South SF hills are in the path, consequently signal strength is weak. We finally bought an outdoor FM antenna from Radio Shack a few years ago (about $25 to $30 at the time). It is about 8 to 10 elements (I'm at work so I can't check). However, I just checked and Radio Shack doesn't have it in their current catalog. Winegard (a very common antenna brand) makes a two-element omnidirectional (think X-shaped) FM antenna #PR-6010, a 4-element yagi #PR-6000 and a 10-element yagi #HD6065P.
If you have good line-of-sight to the transmitting antenna in question, the omnidirectional antenna will probably work great. If there is anything to interfere with the signal path, one of the yagi antennas may be required since they will give more signal gain.
For the shop (garage), I tried a table radio with built-in FM antenna. It would work well for a day or so and then fade out. I kept trying it in different locations, but could never find a spot in the shop that would give consistent reception. Finally, I connected an old outdoor TV antenna to it (we have cable now) and it works great.
Good luck,
Richard Baker
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